[OSM-talk-be] The Gisteq GPS USB Dongle

[Patrick Weemeeuw]

Perhaps I should comment a bit with my experienes using a USB GPS 
dongle with a linux device (eee, with solid state disk)

it's lots of fun, if, and that's a big if, you like tinkering with all 
kinds of things.

It's nice to be able to integrate in one device voice recording, track 
recording, navigation, even josm editing on the spot...

On the other hand, lots of things will go wrong, or get some 
interesting twist.

E.g. you would assume that callibraton for voice recording is not 
necessary, because the tracking device and the recording device are 
one and the same. Not quite so: it's close, but every now and then a 
frame is skipped, and the gps clock and the computer clock are not 
completely synchronized, and cannot be synched in an accurate way via 
ntp unless you have an old style serial port gps dongle, that is able 
to synch the ticks by dropping carrier detect. You see, in the process 
you learn a lot of interesting things, which may not necessarily speed 
up the mapping effort...

It's also no fun when you discover at home that you lost 4 hours of 
voice recording, because you aborted the application and the file was 
not properly closed (the length in the header is not correct, but 
wait, perhaps we can fix that...). Or because your disk got full...

Currently I'm working on registering waypoints, which is becoming an 
independent hardware project on its own (you see, there is no obvious 
button to push in my setup, because keyboard clicks and mouse clicks 
go to the application that currently has the input focus).

For use under linux, you will want to check whether the device you 
have in mind has binary support in gpsd (the sirfstar iii chipset is 
supported), otherwise, when starting up you'll have to wait, because 
the gps mouse cold starts, without any saved information.

Also, the setup is mostly suited for mapping by car.  something you 
can put in your pocket is much handier when walking or biking.

(just some random thoughts)

-- Patrick

On Tuesday 14 July 2009 11:38:26 Marc Verwerft wrote:
> Hello Marc,
>
> The main difference between the devices that Peter and Luc use and
> you GISTEQ dongle is that the GISTEQ dongle has no builtin memory
> for tracking.
> In other words, they just put their device in their pocket and
> start walking. Later on they connect to a PC and do read out of the
> data to see which path they followed. Your device needs to be
> hooked up to a PC/PDA that will record the GPS track. Personally, I
> prefer a tracking capability on the device (but of course it costs
> more then).
>
> Regards,
>
> Marc Verwerft
>



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